JTS Broken Airacuda Max .25 Valve Core

Max recently broke valve seat, JTS replaced under warranty, new one broke after a dozen shots. No response from JTS for purchasing another so looking for suggestions. Does anyone make these out of stronger material? Thanks, WM
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That’s frustrating. I don’t know how prevalent the poppet breakage is on the Airacuda but I thought the factory had pretty well worked it out on the DAR platform. By that I mean it was a common failure on the gen 1 (experienced it myself) and then seemed to subside on the gen 2 and 3. The only advice I can offer is take a careful look at the valve spring adjuster and the poppet’s travel.

Referring to the threaded cap that retains the valve spring. If the cap is threaded too far into the valve body, there is a potential for the hammer to overdrive the stem, causing the poppet to reach a hard stop. If that happens, the hammer can drive the stem through the poppet, rupturing it. The location of the break in your photo is consistent with...
Make one out of peek. So strange those are breaking, has to be their manufacturing process compromising the integrity of the material, creating micro fractures from pressing the stem into the head perhaps?

I've made a dozen or so of my own poppets by hand with a drill and never experienced one break like that.

If the rifles under warranty, I would 100% expect JTS to be responsible for making it right, the no response from them is...unacceptable, they're a sponsor here now so you should voice your experience in the industry feedback and give them a chance to respond there.

-Matt
 
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Make one out of peek. So strange those are breaking, has to be their manufacturing process compromising the integrity of the material, creating micro fractures from pressing the stem into the head perhaps?

I've made a dozen or so of my own poppets by hand with a drill and never experienced one break like that.

If the rifles under warranty, I would 100% expect JTS to be responsible for making it right, the no response from them is...unacceptable, they're a sponsor here now so you should voice your experience in the industry feedback and give them a chance to respond there.

-Matt
Matt,
The bright side of my experience with the Airacuda Max .25, from purchase in October 2022, has been the knowledge I've accumulated trying to get it to work properly. My other PCPs haven't asked a thing, other than an HS adjustment, but what do you learn from that? I'll have to commend JTS Technical Department for prompt, courteous customer service, very reminiscent of FX-USA. Really impressed with efforts to accommodate and helpfulness. Agree that better material is needed for valve core, hopefully someone will have something available. WM
 
Matt,
The bright side of my experience with the Airacuda Max .25, from purchase in October 2022, has been the knowledge I've accumulated trying to get it to work properly. My other PCPs haven't asked a thing, other than an HS adjustment, but what do you learn from that? I'll have to commend JTS Technical Department for prompt, courteous customer service, very reminiscent of FX-USA. Really impressed with efforts to accommodate and helpfulness. Agree that better material is needed for valve core, hopefully someone will have something available. WM

Being it should be covered by the 3 year warranty, I'd personally be concerned if they aren't promptly addressing your issues, certainly doesn't appear to be a user error causing the failure.

Glad you're happy with the experience from JTS, and I don't doubt someone here could knock you out a new poppet, but other members may not appreciate them leaving you high and dry within their warranty period...

-Matt
 
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That’s frustrating. I don’t know how prevalent the poppet breakage is on the Airacuda but I thought the factory had pretty well worked it out on the DAR platform. By that I mean it was a common failure on the gen 1 (experienced it myself) and then seemed to subside on the gen 2 and 3. The only advice I can offer is take a careful look at the valve spring adjuster and the poppet’s travel.

Referring to the threaded cap that retains the valve spring. If the cap is threaded too far into the valve body, there is a potential for the hammer to overdrive the stem, causing the poppet to reach a hard stop. If that happens, the hammer can drive the stem through the poppet, rupturing it. The location of the break in your photo is consistent with this type of failure.

Looking at this video:
and seeing how far the guy is threading it in, it looks like something to take into consideration.

Note also that it’s possible for a cap like this to self-adjust over time, and actually get tighter. I wouldn’t believe it if I hadn’t seen it myself. I apply a little threadlocker to make sure it stays put. The threads need to be completely clean of any lubricant. Anodized aluminum is considered an inactive material for threadlockers so give it some time to cure before putting it to use.
 
Solution
That’s frustrating. I don’t know how prevalent the poppet breakage is on the Airacuda but I thought the factory had pretty well worked it out on the DAR platform. By that I mean it was a common failure on the gen 1 (experienced it myself) and then seemed to subside on the gen 2 and 3. The only advice I can offer is take a careful look at the valve spring adjuster and the poppet’s travel.

Referring to the threaded cap that retains the valve spring. If the cap is threaded too far into the valve body, there is a potential for the hammer to overdrive the stem, causing the poppet to reach a hard stop. If that happens, the hammer can drive the stem through the poppet, rupturing it. The location of the break in your photo is consistent with this type of failure.

Looking at this video:
and seeing how far the guy is threading it in, it looks like something to take into consideration.

Note also that it’s possible for a cap like this to self-adjust over time, and actually get tighter. I wouldn’t believe it if I hadn’t seen it myself. I apply a little threadlocker to make sure it stays put. The threads need to be completely clean of any lubricant. Anodized aluminum is considered an inactive material for threadlockers so give it some time to cure before putting it to use.

Vibratite VC-3 may be a better answer for thread creep.

I had broken a G2 poppet and Aim Sports sent me a replacement gratis. I copied it and it fit my G3. Not sure if it will fit my MAX.

They are pretty straightforward to make, I choose peek due to less stiction.
 
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That’s frustrating. I don’t know how prevalent the poppet breakage is on the Airacuda but I thought the factory had pretty well worked it out on the DAR platform. By that I mean it was a common failure on the gen 1 (experienced it myself) and then seemed to subside on the gen 2 and 3. The only advice I can offer is take a careful look at the valve spring adjuster and the poppet’s travel.

Referring to the threaded cap that retains the valve spring. If the cap is threaded too far into the valve body, there is a potential for the hammer to overdrive the stem, causing the poppet to reach a hard stop. If that happens, the hammer can drive the stem through the poppet, rupturing it. The location of the break in your photo is consistent with this type of failure.

Looking at this video:
and seeing how far the guy is threading it in, it looks like something to take into consideration.

Note also that it’s possible for a cap like this to self-adjust over time, and actually get tighter. I wouldn’t believe it if I hadn’t seen it myself. I apply a little threadlocker to make sure it stays put. The threads need to be completely clean of any lubricant. Anodized aluminum is considered an inactive material for threadlockers so give it some time to cure before putting it to use.
Watched this video several times, his valve spring cap depth was 18.9mm, mine 20.10mm, had no idea about self-adjust, likely problem. Just love this forum, you help some, some help you! WM
 
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Vibratite VC-3 may be a better answer for thread creep.

I had broken a G2 poppet and Aim Sports sent me a replacement gratis. I copied it and it fit my G3. Not sure if it will fit my MMAX.

They are pretty straightforward to make, I choose peek due to less stiction.
Anyone make replacements in Delrin or Peek, like Motorhead suggests?
 
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Being it should be covered by the 3 year warranty, I'd personally be concerned if they aren't promptly addressing your issues, certainly doesn't appear to be a user error causing the failure.

Glad you're happy with the experience from JTS, and I don't doubt someone here could knock you out a new poppet, but other members may not appreciate them leaving you high and dry within their warranty period...

-Matt
JTS was on fire with my original request, couldn't have been more polite and accommodating, impressed the heck out of me. Awaiting reply on yesterday's e-mail request, even willing to purchase, sounds like self-adjusting valve spring cap is culprit. How did you know about tight fitting metal rod, tried freezing overnight, then mild hairdryer heating of valve core, no luck. Ended up sanding metal edge for straight start, then bench vise to finish. WM
 
JTS was on fire with my original request, couldn't have been more polite and accommodating, impressed the heck out of me. Awaiting reply on yesterday's e-mail request, even willing to purchase, sounds like self-adjusting valve spring cap is culprit. How did you know about tight fitting metal rod, tried freezing overnight, then mild hairdryer heating of valve core, no luck. Ended up sanding metal edge for straight start, then bench vise to finish. WM

Oh if its only been a day than that isn't a big deal, I thought more time had passed between correspondence or lack there of.


That is a frustrating method for a valve end cap to screw in, with no definitive stop for the inlet insert to torque against. Definitely a non-user friendly manufacturer design flaw that warrants replacement under warranty. Instructions should be provided as for proper seating depth like in the above video so users aren't repeatedly snapping poppets.

Another way to test that your valve inlets seating depth isn't too great is to ensure you have around 4mm of poppet travel prior to it bottoming out, 5mm would even be healthier to protect against over strikes. Being a conventional valve (iirc), this seating depth shouldn't be too imperative other than allowing a healthy amount of travel for the poppet without bottoming out.

-Matt
 
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Oh if its only been a day than that isn't a big deal, I thought more time had passed between correspondence or lack there of.


That is a frustrating method for a valve end cap to screw in, with no definitive stop for the inlet insert to torque against. Definitely a non-user friendly manufacturer design flaw that warrants replacement under warranty. Instructions should be provided as for proper seating depth like in the above video so users aren't repeatedly snapping poppets.

Another way to test that your valve inlets seating depth isn't too great is to ensure you have around 4mm of poppet travel prior to it bottoming out, 5mm would even be healthier to protect against over strikes. Being a conventional valve (iirc), this seating depth shouldn't be too imperative other than allowing a healthy amount of travel for the poppet without bottoming out.

-Matt
45Bravo's video reflects a depth of 18.9mm, think thread locked @ 18.5mm should work. Agreed, "self-adjusting" to valve core breakage isn't a winning program, might explain accuracy issues, as well. Once again, at least for me, Airacuda Max ownership means learning PCPs. WM
 
45Bravo's video reflects a depth of 18.9mm, think thread locked @ 18.5mm should work. Agreed, "self-adjusting" to valve core breakage isn't a winning program, might explain accuracy issues, as well. Once again, at least for me, Airacuda Max ownership means learning PCPs. WM

Certainly could explain a bit of accuracy issues, or fps shifting over time. Due to the possible nature of part dimension variability, double check the poppets travel prior to bottoming out if possible, its a better way to measure and calibrate than how it was done in the video. 4-5mm should be plenty of travel to avoid bottoming out the bottom while aired up and shooting.

-Matt
 
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Certainly could explain a bit of accuracy issues, or fps shifting over time. Due to the possible nature of part dimension variability, double check the poppets travel prior to bottoming out if possible, its a better way to measure and calibrate than how it was done in the video. 4-5mm should be plenty of travel to avoid bottoming out the bottom while aired up and shooting.

-Matt
Thanks, will do, appreciate your help! WM
 
Anyone make replacements in Delrin or Peek, like Motorhead sugsurprised!
Just mic the stem and send me the broken one and I'll make a Ti/peek one for you.

I only have 1 piece of Ti left.

I'm lost by all this talk of binding the post to the valve, it's just press fit.
 
Just mic the stem and send me the broken one and I'll make a Ti/peek one for you.

I only have 1 piece of Ti left.

I'm lost by all this talk of binding the post to the valve, it's just press fit.
Thanks, very kind of you. Will give JTS a few days to respond, would prefer sending new valve core for a Ti/peek redo. (Messed up my originals with Krazy Glue repair attempt.) I'm lost too with the post to valve fit, as in how is having to seat post with bench vice not a stress on the plastic? Thanks again, appreciate your generous offer, WM
 
The fitting operation is easy; push the valve stem in until it bottoms out with the hammer spring fully compressed, measure the extension past flush and remove the extra stem.

This way, the stem cannot get bottomed out.

The JTS is not picky about minimum stem length, it responds more to the regulator pressure and dwell doesn't seem to be affected.
 
The fitting operation is easy; push the valve stem in until it bottoms out with the hammer spring fully compressed, measure the extension past flush and remove the extra stem.

This way, the stem cannot get bottomed out.

The JTS is not picky about minimum stem length, it responds more to the regulator pressure and dwell doesn't seem to be affected.
PM'd picture of glued up OEM, I'll mail if any hope to copy. WM